Calk attachment for crutches.



s. H. APPELMAN.

QALK ATTACHMENT FOR GBUTGHES. APPLICATION FILED MAY 20, 1913.

1,090 ,960. Patnted Mar.24,191l

which the crutch is UNITED STATES PATENT rich.

SAMUEL H. APPELMAN, OF BLOOM SBURG, PENNSYLVANIA.

CALK ATTACHMENT ron czeuronns.

Specification of Letters Patent. Application filed May a0, 1913. SerialNo. 768,893.

Patented lllar. 24:. 1914.

To (ZZZ whom it may concern Be it known that T, Sat rum; Arron MAN,citizen of the United States, residing at Bloomsburg, in the county ofand State of Pennsylvania, have invented certain new and usefulImprovements in Calk'Attachments for Crutches, of which the following isa specification.

My invention, relates to new and useful improvements in crutches of thetypein provided with a sharp steel point or calk w ich can bereadilyextended beyond or withdrawn into the lower end of the crutch withoutremoving the crutch from beneath the arm.

= The primary object of my invention is to provide a novel form of latchfor normally holding the rod in withdrawn position frictionally and soarranged that it will automatically lock the calk in extended position-"when the latter is moved outwardly, the

automatic locking of the latch servingto limit the outward movement ofthe'calk.

With these andotherobjects in view, my inventionw-ill be more fullydescribed, illustrated in the aeeompaniying drawing, andthenspecifically pointe' out in the claims which are attached to andform a part of this application. l I

In the drawings: Figure 1 is a perspective View of my improved crutch;Fi 2 is a fragmentary, longitudinal sectional I View, showing certaindetails of itsconstruction; Fig. 3 is a fragmentary longitudinalsectional view of the staff portion of my crotch showing still furtherdetails of construction;

Fig. 4 is a transverse sectional view taken on the line 44 of Fig. 2,lookin upwardly. Corresponding and like pagts are referred to in thefollowing description and indicated in all the views of the drawing bythe same reference characters. I My invention may be applied to orembodied in the construction of crutches of all types but for the sakeof clearness I have 5 shown the same applied to a conventional form ofcrutch including the spaced side members 10 and 11, the lower ends ofwhich arebrought together to form a common stafi' 12 and the upper endsof which are connected ,and held in proper spaced relation by a crossbar forming a shoulder rest 13.

' The intermediate'portions of the side bars 10 and 11 are connected bya handle .14 which also serves to brace and stiffen the side members andmaintain them in spaced Columbia relation The lower end of the staff 12of the crutch is bound by a ferrule 15 to prevent splintering and theupper end of the staii adjacent the point of merger of the sides 10 and11 is bound with a second ferrule 16. These ferrules are preferablyformed of brass, although any other suitablemetal or material may beemployed in-' stead.

The stafl is provided centrally throughout its length with alongitudinally extending bore 17 and fitting within'this bore is aferrule 18 also preferably formed of brass.

This ferrule mayextend throughout practi' cally the entire length of thestaff portion of the crutch or may terminate slightly above the lowerend thereof, its function being to form a bearing for the operating rodor spur rod 19 which carries the calk 20. This bushing or sleeve 18 notonlyfo-rms a hearing for the spur rod but its'lower portion preventsbinding of the spur rod in the bore through swelling of the crutchduring damp weather. The lower end of the spur rod 19 is provided with athreaded socket to receive the reduced, threaded stud 21 of the calk 20,the body portion of the calk being cylindrical in shape and terminatingat its lower end in a conical point 22. Both the spur rod and calk arepreferably formed of steel and the former should be reasonablyresilient, 'while the latter may be made harder and more highly temperedto insure satisfactory wearing qualities.

A U-shaiped bracket 23, also preferably formed of steel, is secured byscrews 24 between the side portions 10 and 11 of the crutch at a pointslightly below the handle 14, theside portions of said bracket beingdirected downwardly along the inner faces of said members. This bracketis provided at a point slightly in advance or at the rear of the .centerwith a bore 25 equal in diameter to the diameter of the spur rod 19 andsaid rod is extended upwardly through the bore, terminatingat its upperend in a knob or handle 26, preferably formed integrally the bracket,extending longitudinally thereofand communicating at one end with thebore 25 and ending at its opposite end centrally of the bracket, thisslot being slightly less in width than the diameter of the bore. Thespur rod 19 is provided at a-point slightly below its handle 26 with'anencircling channel or groove 28 equal in (1 with the rod. A slot 27 isformed same in place.

' viding squared spaced otherwise secured to the lower face of thebracket at that side adjacent the bore 25 and has its inner end cut-awayarcuately as shown at30 to conform to the adjacent 0rtion of the bore 25with which it is in a ine-' ment. This plate, together. with thebracket, forms' a bearing surface for the :spur'rod during itsmovement'to advance or retract the calk 20. i An angular leaf spring 31is secured by one arm to the lower face of the bearing plate 29 by ascrew 32 which passes through said spring arm, through the bearing plateand partially through the bracket 23. The spring is further secured inplace and held against all pivotal movement about i-the screwbyextending one reduced (and 33 into a recess 34 formed in the adjacentside portion of the bracket 23. The opposite arm of extends inwardly anddown-,

this spring wardly engaging against the spur rod to constantly tend toforce the same into the slot 27. i- In operation, assuming that theparts are in the position shown in full lines in Fig. 2 of the-drawing,it will be apparent:

against the. spur that the spring 31, pressing .rod 19'as itdoes,'forces t e same into frictional engagement with the adjacentopening of the slot 27 and. so holds the rod frictionally againstmovement. Moreover, inasmuch as the bore 25, through which the rod atthis time extends, is formed slightly away from the center of thebracketand consequently slightly out of vertical alinement with vthebore l'? through which the lower portion of the rodextends theresiliency of the rod itself wiil further act to lock the In thisposition, the lower end of the spur rod, together with the calk carriedthereby is retracted into the lower end of the staff portion of thecrutch and the crutch may therefore be used upon polished floors orother surfaces without danger of mar'r'ing the same because of the calk.

Whenever the person using the crutch encounters an icy or otherwiseslippery surface lie-may however, extend the calk merely by pressingdownwardly upon the knob or handle 26 at the upper end of the spur rodto force the same against the frictional engz-igemcnt between said rodand theend of the slot until the reduced portion 25 reaches theplane ofthe bracket 23 when both the,

action of the spring 31 course be understood that thespur rod is soproportioned that in this position the cal'k is extended a suitabledistance below the lower-end of the crutch staff. The calk may at anytime be again retracted by swinging the upper end of the spur rodagainst the until the spur rod is seated in the bore 25 and by thenpulling upwardly upon the rod to retract the calk.

It will of course be apparent that this invention may be applied eitherto crutches the ordinary cup-shaped rubber tips one 0 which isconventionally shown at 35. In this latter case, of course, the tip willbe provided with a bore 36 in alinement with the bore of the crutchstafl'.

Although I havefully described my invention in all its details, "it willbe understood that I do not intend in any way to having plain woodenterminals or crutches having limit myself to the specific details ofconst'ruction illustrated in the drawing and described in the foregoingspecification, as variousminor changes, within the scope of the appendedclaimsmay be made at any time without in the slightest degree departingfrom the spirit of my invention.

Having thus described the invention, what is claimed as new is:

'1. In a crutch having spaced side members connected intermediate theirlength by a handle and merging at their lower ends nto a staff portionhaving a' longitudinal bore, a bracket extending between the sidemembers and provided with a bore and a longitudinal slot communicatingwith the bore and less in width than the diameter of the bore, the borebeing ofi'set vertically with respect tothe bore of the staff and theremote end of the slot being in vertical alinement with the bore of thestaff, a resilient operating rod carrying a calk at its lowerendslidable through the bore of the bracket and staff to extend orretract the calk below the lower end of the tafl, said operating rodbeing provided wit 1 a reduced portion to permit the seating of the rodin'the slot through the resiliency of the rod when the rod is lowered toextend the calk, and additional means for forcing the rod into the slot.

2. In a crutch having spaced side members connected intermediate theirlength b a handle and merging at their lower ends 1nto a staff portionhaving a longitudinal bore, a bracket extending between the side membersand provided with a bore and a longitudinal slot communicating with 'thebore and less in Width than the diameter of the bore, the bore beingoifset vertically with respect to the bore of the stafi' and the remoteend of the slot being in vertical alinement with the bore of the staiT,a resilient operating rod carrying a calkat its lower end slidablethrough the bore of the bracket and staff toextend or retract the calkbelow the lower endof the staff, said operating rod being provided witha reduced portion to permit the seating of the rod in the slot throughthe resiliency of the rod when the 0 rod is lowered to extend the calk,and additional means for forcing the rod into'the slot, said meansincluding an angular leaf spring secured by one arm to the lower face ofthe bracket and having a reduced end v M Coplei of this patent may beobtained for five cents each, by addressing the commissioner of ratentm.

' Washington, D. 0.

seating in a socket formed in the bracket, the 10 op osite arm of saidspring bearing against the rod. r

In testimony whereof I aflix my signature in presence of two Witnesses.

SAMUEL H. APPELMAN. [1,. s] Witnesses:

K. OARLo'rTA MOYER, H. Mom. SMITH.

